Which of the following statements about natural rubber is true?
- (A) It is a polymer of 2,2-dimethyl-1,3-butadiene (isoprene).
- (B) On an average, it contains about 5000 isoprene units.
- (C) All double bonds in natural rubber are trans.
- (D) Gutta-percha is a naturally occurring isomer of rubber in which all the double bonds are cis.
The Correct Option is B
Solution and Explanation
Natural rubber is a linear polymer of 2-methyl-1,3-butadiene (isoprene). It is also called cis-1,4-polyisoprene. On an average, it contains 5000 isoprene units. All the double bonds in natural rubber are cis.
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